<html>
  <head>
      <script>
          function go() {
            document.getElementById("described-by-dialog").removeAttribute("hidden");
          }
      </script>
  </head>
  <body>

    <div id="described-by-dialog" role="dialog" aria-describedby="dialog-describedby-label" hidden>
      <h2 id="dialog-describedby-label">Described by dialog title</h2>
      <p>Dialog content:</p>
      <div>
        <input type="text" id="described-by-dialog-focus-element">
      </div>
    </div>

  </body>
</html>
